Catalytic reactors allow to enhance intensity of chemical reactions, to reduce required temperatures and pressures in the reaction areas, to perform otherwise impossible reactions, etc. The representative examples of catalytic reactors are fuel cells, automotive catalytic converters, metal-air batteries, fuel reformers.
The reacting substances are usually fluids and gases which must come into contact with the catalytic material (catalyst) for it to perform its catalytic function. Therefore, in order to improve performance of the catalytic reactors, the effective contact surface of the catalyst has to be increased and/or the flow of the reacting substances contacting with the catalyst surface has to be intensified.
A straightforward increase of the contact surfaces results in unacceptable large sizes of the reactors and in a need for large amounts of the expensive catalytic materials. As a result, in many cases catalytic reactors employ supporting structures having a multiplicity of small cross sectional area passages (capillary and/or porous) whose surfaces are embedded with numerous minute particles of the catalyst. This arrangement increases effective contact surface area while maintaining a reasonable size. However, such an arrangement increases resistance to flow through the catalytic reactor. The increased flow resistance results in increasing back pressure (thus, loss of power) in automotive catalytic converter applications or in the need to increase sizes of the passages (thus, the size of the reactor), and/or size, cost, and energy consumption of the auxiliary pumps, e.g. in fuel cells.
This invention, as described and claimed below, is aimed for elimination of the above-quoted shortcomings of the catalytic reactors.